Data in green cells provided by the manufacturer
or observed; data in the blue cells were measured.

The Cogage stock fan is a fairly typical looking fan with seven translucent
blades with mild curvature. Their trailing edges are almost completely parallel
with the struts, which suggests high tonality might be a characteristic. The
fan is also very light, weighing in at only 90 grams, 20~30 grams less than
most 120 mm fans.

TRUE Spirit Stock Fan Measurements

Voltage

Speed

SPL @1m

12V

1690 RPM

31~32 dBA

9V

1320 RPM

24 dBA

7V

1050 RPM

17 dBA

6V

870 RPM

14~15 dBA

5V

710 RPM

12 dBA

Measuring mic positioned 1m at diagonal angle from
the intake side of the fan.
Ambient noise level: 11 dBA.

The fan's acoustic character was generally buzzy and at close proximity
there was a noticeable wobble. It also had a tendency to rattle at 12V, possibly
due to its lack of mass, and was very loud at 31~32 dBA. As the fan speed was
decreased, the buzzing became less distracting but didn't vanish until it reached
about 6V. The fan became quiet at about 7V, measuring 17 [email protected] It was virtually
inaudible at 5V.

The TRUE Spirit stock fan measured 17 [email protected] at 7V. It had some tonal
elements as indicated by the sharp spikes in the 300~600 Hz range.

Data in green cells provided by the manufacturer
or observed; data in the blue cells were measured.
* specifications when paired with Fan Mate 2 controller (max. 11V)

The Zalman stock fan is similar to the one included with the CNPS10X. It is
a dual ball bearing model with a black frame and only one set of corners (the
ones on the intake side have been omitted), but despite this fact, the fan is
a fairly hefty 130 grams.

CNPS10X Quiet Stock Fan Measurements

Voltage

Speed

SPL @1m

12V

1570 RPM

27 dBA

9V

1230 RPM

19~20 dBA

7V

970 RPM

14 dBA

5V

680 RPM

12 dBA

Measuring mic positioned 1m at diagonal angle from
the intake side of the fan.
Ambient noise level: 11 dBA.

At full speed, the Zalman stock fan sounded very buzzy with a slight flutter
that sounded like soft is chafing against the blades. At 9V, the buzzing turned
into a low-pitched hum,and the flutter started to fade. It became what we would
consider quiet starting at about 8V, and at 7V it was pleasantly smooth and
barely audible at one meter's distance. Of our two review samples, the Zalman
fan was smoother and quieter in general than the Cogage fan.